Pneumatic machine gun adapter for practicing



A. SCHMIDT Aug. 5, 1941.

PNEUMATIC MACHINE GUN ADAPTER FORl PRACTICING Filed sept. 1e, 1937 2 sheetssheet 1 n m :WN EN w. M. .w 7 m Mm ..m as Www M i. I M .rw4 :n 7 7 A T. I '1.... if.

Aug. 5, 1941. A. SCHMIDT 2,251,835

PNEUMATIC MACHINE GUN ADAPTER FOR PRACTICING Filed Sept. 16, ,1937 2 Sheets-Sheet 2 554 FIGA l .l l, l, In', L

'mw-:NT DR; ADAM SCHMIDT BY'KML A. A ru ATTORNE Patented Aug. 5, 1941 PNEUMATIC MACHINE GUN ADAPTER Fon PRACTIGING Adam Schmidt,T Vienna, Austria Application v 9 Claims.

This invention relates to means for adapting machine-guns and machine-rides for shooting pellets with the aid of compressed air for practicing purposes, and provides a particular construction of the adapting mechanism disclosed in the copending application Serial Number 113,216 filed November 28, 1936 which matured into Patent No. 2,110,509, with the object'of enabling the adapting mechanism toV bealso' tted to machine firearms of the type in which there isY no space axially behind the barrel for the provision of a recoil piston operated by compressed air. In a large number of the known types of machine-gun and machine-rie, the repeating action when tiring live ammunition is produced by conducting the high pressure gases behind the projectile in the barrel into a cylindrical chamber adjacent thefbarreLfwhere' they impinge against the end of a recoil piston or recoil rod and force this latter back against the action of a restoring spring. .The port opening' out of the barrel and communicating with the gas recoil chamber is generally "provided approximately within the foremost third of the length of the barrel. In rearms of this description the reciprocating movement of the recoil piston or recoil rod under the in'uence of the restoring spring and of the recoil impulses set up by the gas expansion in the recoil chamber effects the movementl and the'opening and closing of the breech. Owing to the positioning of the repeating mechanism at the side, out of alignment with the barrel there is no room in these firearms, directly behind the barrel, lor the provision of adapting means according to Patent Number 2,110,509. For this reason `the adapting means are lsomodi1ied, in accordance with the present invention, that they are also suited for use in connection with rearms rof the described type.l For this purpose the loading and shooting oli rammer, which moves the pellets forward in the barrel, is separate andV distinct from the control piston which effects the movement of the breech-closing mechanism and which produces the recoil kick. The iiring-oi rammer and the control piston aredisposed in different cylinders, the ring-off rammer being longitudinally movable behind and in axial alignment with the barrel of the firearm, while the control piston, and a controlling slide valve if such be used, works in a cylinder mounted in any desired position, for instance at the side of the rearm.

A form of construction embodying the invenseptember 16, 1937, seria1No.164,o94 In Austria August 26, 1937 (ci. ss-e) tion is shown by way of example in the accompanying drawings, in Which: y

Fig. 1 shows, in longitudinal section and partly` in side elevation, a machine-gun with Ythe adapting means according to ,the invention fitted thereon.

Fig. 2 shows, likewisein section, a modiedform of the adapting means a-ccording to the invention.

. Fig. 3r shows a detail of the mechanism villustrated in Fig. 1.

Fig. 4 shows another detail of the mechanism according to Fig. 1. v Referring to the drawingsfthere is provided v adjoining the rear en-dvof the barrel I, which is generally furnished with a liner to reduce the'.

calibre for the purpose of practice shooting with pellets, a cylinder 2 in which the firing-off rammer is longitudinally movable. This iiring-off` rammer, 3, slides, during its movement, with ,itsv front end past the discharge aperture or orifice.

of the pellet magazine into the barrel, and is provided, for the purpose of expelling the pellets from the` firearm, with a passage 4 intowhich the compressed air can enter through the port 5 in the cylinder 2. The port 5 communicates with'the compressed air admission valve 6. This valve is controlled, through the intermediary of` a stem 1, by the iiring-oi rammer itself which 8. Behind the compressed air admission vvalve there is branched oii a compressed air pipe I0.

which leads to a cylinder Il mounted at .the side Iof the machine-gun. In this cylinder ,operates the control piston I2 which generates the recoil kick. A spindle I3 is attached to the piston I2 and extends out of the cylinder infront; its forward end carries to the lever I4 ofthe repeating mechanism which lever is provided a lug, I5. Within the cylinder I I there is mounted, longitudinally movable on the spindle I3, a slide valve IB for controlling the .admission of air into the cylinder. The slide valve I6 is moved to and fro by abutments or shoulders I'I, I8 provided, respectively, on the spindle and on the end of the piston. The outlet for the compressed air from the cylinder II leads through the port I9 and the pipe 2li to the pellet magazine 9, so that the intermittent impulses of the exhaust are the barrel of the` rearm. Parallel with this air pipe there may also be provided an exhaust*V pipe discharging directly into the open. The lug vI5 reciprocated with the piston I and spindle I3 coacts with a lug 2| provided for this purpose is provi-ded with oblique surfacesutilized for driving the pellets forward towardsdirectly adjacent each Yother '(see Fig. 2).

in the usual manner on the recoil rod 22 of the firearm when adapted for firing live ammunition in which case this rod fulfils the function mentioned above. Lug 2| moves in a slot 33 and projects therefrom. Rod 22 extends with its front end (not shown in the drawings) into a cylinder disposed adjacent the barrel of the firearm, into which the gases generated in the barrel are conducted, and is forced back by these gases against the force of the restoring spring 34 disposed inside the firearm substantially parallel to the cylinder II. Spring 34 abuttingly engages Y rod 22 which, for this purpose, is provided withv a projection 35. During this rearward movement the recoil rod' eects, by means of various lugs and bears sur-r faces, the movement of different parts of the firing-off mechanism required in the'course of the firing operation. The described adapting means, for converting the machine-guns into a pellet-shooting practising firearm, makes use of the recoil rod 22 in the first place to effect a coupling between the piston I2 and the firing-off rammer 3, in that the firing-off rammer 3 is held fast Vwith its knob-like rear end 23 between lugs 24 on the recoil rod while the piston AI 2 is coupled, by Ameans of the lugs I5 and 2I, for reciprocal movement with the recoil rod. In addition, the pressure of the restoring spring is transmitted, through the recoil rodv22 and lug 2I, to the control piston I2. Y

'The mode of operation of the adapting means according to the present invention is the same as that of the device'disclosed in the co-pendingr application Serial Number 113,216, whichv maturedinto Patent No.v 2,110,509. When the trigger is pulled the recoil rod moves forward under the influence ofthe restoring spring, and takes ,theVring-off rammer 3 and the control piston I2 along with it in this movement. In moving forward,the firing-olf rammer opens the compressed airadmission Valve E. As soon as the entire'moving mechanism reaches approximately its foremost end position the compressed air canpass through the opened admission valve on the one handthrough the port 5 into the passage 4 in the firing-off rammer to shoot the pellet out ,of the barrel, and on the other hand through the pipe I0 into the cylinder II where in the meantime theY slide valve I6 has been movedinto its foremostpositio'n so that the exhaustpipe I9 is closed off and the entering compressed air drives the piston |2 back and thereby operates the entire firing-off mechanism. This rearward movement which, in consequence of the large cross-section of the piston I2, produces just as powerful a kick as the recoil movement of the firing mechanism in the normal firearm when Ausing vlive ammunition takes the piston I2 andalso the recoil `rod 22 and the ring- 01T -rammer 3, against. the force of the restoring spring, into their rearmost end position. Just before this position is reached, the slide Valve I6 opens the exhaust pipe I9, 23, so that a pui of compressed air enters the pellet magazine and pushes the train of pellets on towards the barrel .of the firearm, after which the described cycle may be repeated. y

In a modified machine-gun design it is'possible -to'place the cylinder 2 for the firing-off rammer andthe cylinder II for the control piston In this case the paths along which airis conducted between the two cylinders are simplified. rThe This is illustrated in Figure V4. -v

piston by I2', and these two parts are interconnected by suitable parts of the firing-off mechanism, for example by means of a lug 2|' of the recoil rod 22' which lug engages lug I5 of piston rod I3. In this case the compressed air admission valve 6 discharges directly into the cylinder II and is controlled by sloping surfaces 25 provided on an Yelement attached to the spindle or stem I3' of the control piston. From the valve 6 a passage 26 leads on the one hand into the space 21 in front of the piston, and on the other Yhand through a recess 28 in the piston to the port 29 and thence into the firing-off passage of the rammer 3'. 30 denotes a port which is intended to establish equality of pressure betweenthe spaces in front of the control piston and the firing-off rammer, 3| denotes the pellet feed passage, and 32 the exhaust port. The exloading'rammeris denoted -by 3 and the control '75 haust port 32 may either discharge into the open as indicated in Fig. 2 or be connected up to the pellet magazine in a manner similar to that shown in Fig. 1. A further possibility 'is to close the pressure equalizing port 30 and to take the exhaust passage into the space in front of the firing-01T rammer 3 and only from there to th pellet magazine.

When the iiring-off mechanism is released by pulling the trigger this mechanism is forced forward by the action of the restoring spring V34' which is diagrammatically shown only, until the control piston I2 is near its foremost end position and the compressed air admission Valve 'I is opened by the sloping surfaces 25. The compressedair then iiows through the passage 26,v past the recess 28 in the control piston, through the communicating port 29, to the firing 01T vram'-` mer, and passes through the passage in this'latter into the barrel so that the pellet at the rear pellet has come into position in the barrelv through the feed pipe 3|, so that `the next shot can be fired in the same manner as the last.'

I claim: n

1.` A mechanism for adapting machine firearms for shooting pellets with the aid of compressed air for practicing purposes, comprisingk a cylinder, a loading and firing-off rammer o'p-l erating in said cylinder, a second cylinderV having an axis -spaced from and parallel to the axis' of Vsaid rst mentioned cylinder, a piston mechanically connected with said rammer and disposed in said second cylinder, compressedairinlet means and compressed air outlet means con-.- nected with said second cylinder forward ofV said piston, compressed air ow control means disposed within said second cylinder forward of said piston and adapted to be operated by said piston.

and to admit compressed air from said inlet means to said vsecond cylinder and to simultaneously close said compressed air outlet means for forcing said lpistonV and said rammer into loading position by means of compressed air.

2. A mechanism for adapting machine firearms` for shooting pellets with the aid of compressed air for practicing purposes, comprising ay cylin;` der, a loading and firing-off rammer operating in said cylinder, another cylinder having anaxis which does not coincide with the axis of said first mentioned cylinder, a piston operating in said other cylinder and being mechanically connected with said rammer, a source of compressed air, an inlet port connected with said source and being positioned in said other cylinder, and an outlet port for compressed air connected with said other cylinder, a slide valve in said other cylinder associated with and operated by said piston and opening said inlet port and admitting compressed air to said other cylinder and simultaneously closing said outlet port whereupon the compressed air forces said piston and said rammer connected therewith back into loading position.

3. A mechanism for adapting machine firearms for shooting pellets by means of compressed air, comprising a reciprocatingly operating loading and iiring-of rammer mechanism comprising a laterally projecting lug, a cylinder, a piston operating in said cylinder and having an extension provided with a laterally projecting lug engaging said first mentioned lug and mechanically interconnecting said piston and said rammer mechanism, a source of compressed air, an inlet port connected with said source and being positioned in said cylinder, and an outlet port for compressed air in said cylinder, port control means associated with and being operated by said piston and opening said inlet port and admitting compressed air to said cylinder and simultaneously closing said outlet port, whereupon the entering compressed air forces said piston and said rammer connected therewith back into loading position.

4. A mechanism for adapting machine firearms for shooting pellets by means of compressed air, comprising a cylinder, a piston operating in said cylinder and having a loading and iiringoff rammer connected therewith, another cylinder having an axis which does not coincide with the axis of said iirst mentioned cylinder, a piston operating in said other cylinder and being mechanically connected with said iirst mentioned piston, resilient means connected with one of said pistons, a source of compressed air, an inlet port connected with said source and being positioned in said other cylinder, and an outlet port for compressed air in said other cylinder, port control means associated with and being operated \by said piston and opening said inlet port and admitting compressed air to said other cylinder and simultaneously closing said outlet port, whereupon the entering compressed air forces said piston and said rammer connected therewith back into loading position against the action of said resilient means.

5. A mechanism for adapting machine firearms for shooting pellets by means of compressed air, comprising a cylinder disposed coaxially and connected with the barrel of the firearm, a loading and liring-oif rammer reciprocatingly movably disposed in said cylinder and having a compressed air channel for conducting compressed air to and iiring a pellet, a second cylinder, compressed air supply means connected with both said cylinders, an air admission valve in said supply means adapted to be directly operated by said rammer for admitting compressed air to said rst mentioned cylinder and to said air channel when said rammer is in ring-oi position, and a compressed air actuated piston laterally operatively connected with said rammer and adapted to move said rammer back into loading position after firing of a pellet.

6. A mechanism for adapting machine firearms for shooting pellets by means of compressed air, comprising a cylinder, a piston reciprocatingly operating in said cylinder, another cylinder, a piston operating in said other cylinder and being laterally operatively connected with said first mentioned piston, a source of compressed air connected with one of said cylinders, an air admission valve connected with said source and being operatively connected with and operated by one of said pistons and being opened and admitting compressed air from said source into both said cylinders when said piston with which said valve is connected is in firing-ofi position, the compressed air admitted to said first mentioned cylinder ring-oi a pellet and the air admitted to said second mentioned cylinder returning said pistons to loading position.

7. A mechanism for adapting machine iirearms for shooting pellets by means of compressed air, comprising a cylinder, a loading and firingoff rammer reciprocatingly operating in said cylinder, another cylinder, a piston operating in said other cylinder and being laterally operatively connected with said rammer, a source oi compressed air connected for air iiow with said cylinders, an air admission valve connected for air flow with said source and being operatively connected with and operated by said rammer and being adapted to be opened and to admit compressed air from said source into both said cylinders when said rammer is in firing-off position, the -compressed air admitted to said first mentioned cylinder firing-off a pellet and the air admitted to said second mentioned cylinder returning said piston and rammer into loading position.

8. A mechanism for adapting machine iirearms for shooting pellets by means of compressed air, comprising a reciprocatingly operating loading and ring-off rammer, a cylinder, a piston operating in said cylinder, said rammer and piston being abuttingly connected with one another, a source of compressed air, an inlet port and an outlet port for compressed air positioned in said cylinder and being connected with said source, port control means in said cylinder and being operatively connected with and operated by said piston, said control means, in iiring-oi position of said piston, opening said inlet port and the compressed air entering said cylinder forcing said piston and said rammer cooperating therewith back into loading position.

9. A mechanism for adapting machine iirearms for shooting pellets by means of compressed air, comprising a reciprocatingly operating loading and firing-off rammer, a cylinder, a piston operating in said cylinder, said rammer and piston being disconnectably connected with one another, a source of compressed air, an inlet port and an outlet port for compressed air disposed in said cylinder and being connected with said source, port control means disposed in said cylinder and being operatively connected with and operated by said piston, said control means, in ring-oi position of said piston, opening said inlet port and the compressed air entering said cylinder forcing said piston and said rammer cooperating therewith back into loading position.

ADAM SCHMIDT. 

